Application of infrared thermography in the characterization of voids and honeycomb in concrete structure

2014 ◽  
Vol 5 (2) ◽  
pp. 107-119 ◽  
Author(s):  
Naouar Laaidi ◽  
Sougrati Belattar
Keyword(s):  
Numerical Simulation ◽  
Concrete Structure ◽  
Design Methodology ◽  
Concrete Slab ◽  
Reinforced Concrete Slab ◽  
Content Type ◽  
Great Utility ◽  
Simulation Based ◽  
Temperature Development

Purpose – The purpose of this paper is mainly the quantitative and the qualitative analysis of a reinforced concrete slab containing two types of delaminations: voids and honeycomb, with different sizes and depths. Design/methodology/approach – In this paper the paper adopts the infra-red thermography as a sounding method. It is used as a tool to estimate the change in temperature or thermal contrast induced by the presence of a defect in specimen besides using numerical simulation based on FEM to develop the prediction of temperature development in concrete structure. Findings – This study shows that the numerical methods can be used to evaluate and validate the experimental results. The coupling of the simulation and the experimentation can be of a great utility because it allows predicting the results before beginning the experimentation. Originality/value – The paper finds that the use of FEM in the prediction of temperature evolution in concrete, and the validation of the numerical simulation with the results obtained by the experimental measurements have a key importance in the study of civil engineering structure.

Temperature distribution simulations during electron beam freeform fabrication process based on the fully threaded tree

2019 ◽  
Vol 25 (6) ◽  
pp. 989-997
Author(s):  
Yajun Yin ◽  
Wei Duan ◽  
Kai Wu ◽  
Yangdong Li ◽  
Jianxin Zhou ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Temperature Field ◽  
Electron Beam ◽  
Additive Manufacturing ◽  
Temperature Distribution ◽  
Design Methodology ◽  
Content Type ◽  
Freeform Fabrication ◽  
Simulation Based ◽  
Simulation Results

Purpose The purpose of this study is to simulate the temperature distribution during an electron beam freeform fabrication (EBF3) process based on a fully threaded tree (FTT) technique in various scales and to analyze the temperature variation with time in different regions of the part. Design/methodology/approach This study presented a revised model for the temperature simulation in the EBF3 process. The FTT technique was then adopted as an adaptive grid strategy in the simulation. Based on the simulation results, an analysis regarding the temperature distribution of a circular deposit and substrate was performed. Findings The FTT technique was successfully adopted in the simulation of the temperature field during the EBF3 process. The temperature bands and oscillating temperature curves appeared in the deposit and substrate. Originality/value The FTT technique was introduced into the numerical simulation of an additive manufacturing process. The efficiency of the process was improved, and the FTT technique was convenient for the 3D simulations and multi-pass deposits.

Participating by activity or by week in MOOCs

2018 ◽  
Vol 119 (9/10) ◽  
pp. 572-585 ◽  
Author(s):  
Alok Baikadi ◽  
Carrie Demmans Epp ◽  
Christian D. Schunn
Keyword(s):  
Learning Outcomes ◽  
Design Methodology ◽  
Online Courses ◽  
Massive Open Online Courses ◽  
Learning Activities ◽  
Massive Open Online ◽  
Full Spectrum ◽  
Content Type ◽  
Activity Form

Purpose The purpose of this study was to provide a new characterization of the extent to which learners complete learning activities in massive open online courses (MOOCs), a central challenge in these contexts. Prior explorations of learner interactions with MOOC materials have often described these interactions through stereotypes, which accounts for neither the full spectrum of potential learner activities nor the ways those patterns differ across course designs. Design/methodology/approach To overcome these shortcomings, the authors apply confirmatory and exploratory factor analysis to learner activities within three MOOCs to test different models of participation across courses and populations found within those courses. Findings Courses varied in the extent to which participation was driven by learning activities vs time/topic or a mixture of both, but this was stable across offerings of the same course. Research limitations/implications The results call for a reconceptualization of how different learning activities within a MOOC are designed to work together, to better allow strong learning outcomes even within one activity form or more strongly encourage participation across activities. Originality/value The authors validate new continuous-patterns rather than a discrete-pattern participation model for MOOC learning.

Characterization of structure and air permeability of aromatherapic terry textile

2016 ◽  
Vol 28 (1) ◽  
pp. 2-17 ◽  
Author(s):  
Salvinija Petrulyte ◽  
Deimante Vankeviciute ◽  
Donatas Petrulis
Keyword(s):  
Statistical Analysis ◽  
Physical Properties ◽  
Design Methodology ◽  
Air Permeability ◽  
Factorial Designs ◽  
Linear Type ◽  
Content Type ◽  
Mathematical Equations ◽  
Binder Concentration

Purpose – The purpose of this paper is to investigate the physical properties of smart aromatherapic ramie/cotton terry fabrics containing microcapsules (MC) with essential Eucalyptus oil. Design/methodology/approach – Terry fabrics are manufactured by changing the weft density. The air permeability is determined for grey and microencapsulated textile. The factorial designs are made. For informative experiment the linear type of regression is analysed. Development of physical properties of microencapsulated terry fabrics is discussed. Findings – The air permeability of aromatherapic terry fabrics is determined. All statistical analysis is performed. Appropriate conclusions about the influence of fabric’s structure and microencapsulating process on terry fabric quality are made. Originality/value – To date there are no investigations concerning terry textiles with fragrance MC. This study developed analysis and empiric mathematical equations suitable for evaluating and designing terry fabrics with the air permeability required. Assessment of the influence of fabric’s weft density and binder concentration for the air permeability of terry textile is proposed.

scholarly journals High-growth firms and scale-ups: a review and research agenda

2019 ◽  
Vol 54 (1) ◽  
pp. 96-111
Author(s):  
Guilherme Fowler A. Monteiro
Keyword(s):  
Research Agenda ◽  
Design Methodology ◽  
Scale Up ◽  
High Growth ◽  
Levels Of Analysis ◽  
Future Research ◽  
Content Type ◽  
Growth Firms ◽  
Different Levels

Purpose This paper aims to conduct an extensive review and advances a framework for the literature of high-growth firms (HGFs) and scale-ups. Design/methodology/approach This paper takes the form of a literature review. Findings The author makes three specific contributions. First, he presents a broad review of high growth in firms, shedding light on the different levels of analysis. Second, he advances a characterization of scale-up companies to enable a better basis for discussion. Finally, he identifies gaps in the existing literature and suggest paths for future research. Originality/value The interest in HGFs and those referred to as scale-ups has increased considerably in recent years. Despite this trend, existing studies still have conceptual divergences and a gap separating theoretical inputs from the actual experiences of entrepreneurs.

Modeling the hierarchical structure of secondhand clothing buying behavior antecedents of millennials

2020 ◽  
Vol 15 (4) ◽  
pp. 1679-1708 ◽  
Author(s):  
Maria Esther Medalla ◽  
Kafferine Yamagishi ◽  
Ann Myril Tiu ◽  
Reciel Ann Tanaid ◽  
Dharyll Prince Mariscal Abellana ◽  
...  
Keyword(s):  
Hierarchical Structure ◽  
Current Literature ◽  
Design Methodology ◽  
Structural Modeling ◽  
Buying Behavior ◽  
Theoretical Frameworks ◽  
Content Type ◽  
The Hierarchical Structure ◽  
Holistic Analysis

Purpose Due to the growing dominance of the millennials in the secondhand clothing (SHC) market, it is crucial to understand the dynamics of their SHC buying behavior. Despite such significance, it has yet to be explored in the current literature. To address such a gap, this paper aims to explore the antecedents of the SHC buying behavior of millennials. Design/methodology/approach A purposive survey is conducted to establish relationships between the antecedents. As such, the interrelationships of the antecedents are modeled using the interpretative structural modeling (ISM) approach. Findings Results reveal that SHC antecedents exhibit several characteristics depending upon their characterization of being driving, dependence, linkage and autonomous variables. Originality/value This work pioneers the identification of SHC buying behavior antecedents specifically for the millennial market, as well as in the provision of a holistic analysis of the complex contextual relationships of these antecedents. The findings of this work provide insights that are crucial to the extant literature in developing theoretical frameworks and paradigms that help in understanding the dynamics of the SHC buying behavior. Moreover, such results are beneficial to marketing managers and practitioners in innovating their strategies to capture the millennial market better.

scholarly journals Characterization of the consumer market and motivations for the consumption of craft beer

2018 ◽  
Vol 120 (2) ◽  
pp. 378-391 ◽  
Author(s):  
Naiara Barbosa Carvalho ◽  
Luis Antonio Minim ◽  
Moysés Nascimento ◽  
Gustavo Henrique de Castro Ferreira ◽  
Valéria Paula Rodrigues Minim
Keyword(s):  
Design Methodology ◽  
Metropolitan Region ◽  
Competitive Advantages ◽  
Market Segment ◽  
Consumer Market ◽  
Content Type ◽  
Craft Beer ◽  
Belo Horizonte ◽  
Practical Implications

Purpose The purpose of this paper is to determine the demographic characteristics and habits of craft beer consumers, as well as to identify the motivational factors for consumption. Design/methodology/approach Data were collected through questionnaires applied to 316 Brazilian craft beer consumers, and results were evaluated descriptively and by multivariate statistics. Findings The results of the survey revealed that there is a growing market segment with different buying habits and behaviors compared to traditional beer consumers. Demographically, it was found that these consumers are an attractive part of the beer market in terms of age, schooling and, more importantly, in terms of income, factors that indicate the probability of continued growth in the sector. Research limitations/implications The research was limited to craft beer consumers in the metropolitan region of Belo Horizonte/MG, Brazil. Practical implications The results obtained are important, as they can help new craft breweries, as well as help established industry managers to create strategies related to marketing four Ps in order to increase the consumption of its products, with competitive advantages to the market. Originality/value This research presents the characteristics of the consumers of craft beer, a market segment in evident rise in Brazil, about which there are few studies. In addition, it provides valuable information to both the new beverage manufacturers as well as to the already established entrepreneurs in the market so that they can increase the consumption of their products in a strategic way.

Design and characterization of a T-shaped two-axis force sensor

Sensor Review ◽  
2019 ◽  
Vol 39 (6) ◽  
pp. 776-782
Author(s):  
Liang Zhong ◽  
Feifei Li ◽  
Yuxin Peng ◽  
Qiang Yang ◽  
Mingming Zhang ◽  
...  
Keyword(s):  
Design Methodology ◽  
Simple Structure ◽  
Force Sensor ◽  
The Other ◽  
Strain Gauges ◽  
Content Type ◽  
Sensor Head ◽  
Compact Size ◽  
Basic Performance

Purpose This paper aims to propose a type of T-shaped two-axis force sensor for measuring the forces in x- and z-axes. The developed sensor has a simple structure and can be effectively assembled into compact devices. Design/methodology/approach A T-shaped plate, with both ends fixed on a base, is used as the substrate of the sensor. Eight strain gauges are placed in the root of the plate or near the sensor head, which can construct two full Wheatstone bridges on the upper and lower surfaces of the plate. When the x- or z-axes forces are applied to the sensor head, different deformation can be generated to the strain gauges. Therefore, the two Wheatstone bridges can be constructed with a different configuration for measuring the forces in x- or z-axes, respectively. Findings A prototype was designed and constructed and experiments were carried out to test the basic performance of the sensor. It has been verified that the developed sensor could measure the x- and z-axes forces independently with a high resolution of 2.5 and 5 mN, respectively. Originality/value Only one thin plate was used in the design, the forces in x- and z-axes could be measured independently and simultaneously, which made the sensor with a simple structure and compact size. Experiments were also verified that there was no crosstalk error occurred in one axis when the force was applied to the other axis.

A probability transformation method (PTM) for the dynamic stochastic response of structures with non-Gaussian excitations

2018 ◽  
Vol 35 (5) ◽  
pp. 1978-1997 ◽  
Author(s):  
Giovanni Falsone ◽  
Rossella Laudani
Keyword(s):  
Design Methodology ◽  
Fundamental Property ◽  
Transformation Method ◽  
Computational Effort ◽  
Content Type ◽  
Probabilistic Characterization ◽  
Probability Transformation ◽  
Dynamic Stochastic ◽  
Non Gaussian

Purpose This paper aims to present an approach for the probabilistic characterization of the response of linear structural systems subjected to random time-dependent non-Gaussian actions. Design/methodology/approach Its fundamental property is working directly on the probability density functions of the actions and responses. This avoids passing through the evaluation of the response statistical moments or cumulants, reducing the computational effort in a consistent measure. Findings It is an efficient method, for both its computational effort and its accuracy, above all when the input and output processes are strongly non-Gaussian. Originality/value This approach can be considered as a dynamic generalization of the probability transformation method recently used for static applications.

Characterization of lubrication of asymmetric rollers including thermal effects

2015 ◽  
Vol 67 (3) ◽  
pp. 246-255
Author(s):  
Venkata Subrahmanyam Sajja ◽  
Dhaneshwar Prasad
Keyword(s):  
Power Law ◽  
Thermal Effects ◽  
Design Methodology ◽  
Hydrodynamic Lubrication ◽  
Flow Equation ◽  
Theoretical Problem ◽  
Governing Equations ◽  
Content Type ◽  
The Mean

Purpose – The purpose of this paper is to deal with the qualitative analysis of hydrodynamic lubrication of asymmetric rollers with non-Newtonian incompressible power law lubricants including Newtonian. Design/methodology/approach – The fluid flow governing equations such as equation of motion along with continuity and thermal equations are solved first analytically and investigated numerically by the Runge-Kutta Fehlberg method. Findings – As a result of this work, it is found that there is a significant change in temperature, pressure, load and traction with Newtonian and non-Newtonian fluids. Research limitations/implications – The authors considered incompressible hydrodynamic lubrication of two rigid asymmetric rollers, one of them is assumed to be adiabatic. The convection term of the heat flow equation is taken in its average form. Originality/value – It is a theoretical problem of two heavily loaded rigid cylindrical rollers with cavitations, where the consistency of the power law lubricant is assumed to vary with pressure and the mean film temperature. It has not appeared in the literature.

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